The field of the present invention relates to cooking timers, and, more particularly, timing control circuits which adjust the cooking time for varying temperatures of the heated cooking medium and of the food product. This achieves a uniform degree of doneness, batch to batch, irrespective of these variations.
Cooking is, essentially, the addition of heat energy, i.e., caloric input, to food. The food is cooked when the proper amount of heat input has been achieved. The necessary amount of heat input depends upon the original temperature of the food product being cooked, the total quantity of food being cooked, and the nature of the food product. The rate at which the heat input total is achieved depends upon the temperature of the cooking medium. These, then, are reflected in two factors that must be considered in cooking: first, the temperatures of the cooking medium (which is reduced when a cold food product is put in it) and, second, the characteristics of the food itself.
Certain prior art circuits provide cooking time computation by using a resistance-capacitor ("RC") integrating circuit with the charging voltage of the RC circuit being varied according to the temperature, together with a separate trigger circuit actuated when the voltage across the capacitor reaches a predetermined level. An example is shown in Martino U.S. Pat. No. 3,326,692. Capacitor integrating time varies inversely with temperature, thus compensation for different temperatures of the cooking medium and the food is provided.
The present timing device or cooking computer accomplishes the desired cooking timing for a multiplicity of food types by utilizing a temperature sensitive probe in combination with circuitry that is adjustable for particular food types. The circuitry also is of a unique type in that it provides far greater accuracy in cooking times than has been available in the past.